If you set minimus as a target, you will see the ascending and descending nodes on your orbit, if you create a maneuver on one of them you can match the inclination (angle) of minmus' orbit to make your transfer easier. You use the triangle looking icons to change this.

Right clicking any of these POIs on your orbit (like periapsis, apoapsis, or the ascend/descend nodes) will make them stay visible so you can see what your maneuver is changing.

(after writing this, I can't remember if you have to unlock the maneuver planner in career mode though, it may be a tracking station upgrade if you don't have it.)

It's a complicated game at first, but if you mess around enough it all becomes pretty intuitive.

If you find the contracts a bit stale after a while, there are a bunch of great contract mod packs that focus on building space stations or putting up satellites or scanning planets, etc. I usually just play the science mode and make my own goals though.

I love KSP so much and have played it way too much. There are so many good mods for it that extend the game massively and make it very beautiful. CKAN is a great mod manager btw, it's very easy to use and makes installing/removing mods a breeze.

I'm currently playing with the Kcalbeloh system mod, and it's so much fun to explore and learn a new system.